The present invention relates to an intraoral alarm device which will signal the user whenever the teeth are clenched or ground during times when the jaw should be relaxed. Subconscious clenching and grinding (bruxism) occurs in many people as a result of nervousness both when awake and when sleeping. This results in undue wear of occluding surfaces, the onset of dental caries, muscular tension, headaches and other problems.
It is difficult to discontinue a subconscious practice because constant monitoring is required. If a signal or alarm can be provided to bring the practice to conscious attention, a habit of relaxing the jaw can be substituted.
Some equipment has in the past been devised to measure various occlusal forces, to study mastication, adjust dentures, trace hard-to-localize jaw pain, etc. Shackelford (U.S. Pat. Nos. 3,349,489 and 3,239,935) e.g. describes arcuate devices which are placed in the mouth to measure relative occlusal pressures. These devices contain pressure sensitive resistances which produce electrical signals and can actuate externally located metering devices. Connection from the resistors in the mouth to the metering devices is through multiconducting cable which exits through the lips and is coupled to an external control box. Lauks and Yankell (U.S. Pat. No. 4,629,424) by-pass the problem of the cable by employing a telemetry circuit installed in the removable mouthpiece along with pressure transducers. The telemetry circuit, which operates at radio frequencies, uses the pressure transducers to modulate the radio signal output. An external receiver demodulates the signal and displays it on a meter. Although an improvement over prior art, the system is complex, difficult to tune and requires an external control box.
In signalling the onset of bruxism it would be desirable to have a totally self-contained, intraoral appliance which can be worn during waking or sleeping hours without interfering with the normal activities or sleep of the individual. It is one objective of the present invention to incorporate pressure sensing means, a delay oscillator, a sound producing device and a power supply in a compact-enough form to fit into an introral appliance without causing user discomfort. It is a second objective to provide an appliance which the patient himself can readily insert, remove and keep clean during day or night use. It is a third objective to provide a device which will signal bruxism without disturbing others. These and other objectives will become apparent from the following description and the drawings.